<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
      class="page-nav-bar"
      left-arrow
      title="黑马头条"
      @click-left="$router.back()"
    ></van-nav-bar>
    <!-- /导航栏 -->

    <div class="main-wrap">
      <!-- 加载中 -->
      <div v-if="loading" class="loading-wrap">
        <van-loading
          color="#3296fa"
          vertical
        >加载中</van-loading>
      </div>
      <!-- /加载中 -->

      <!-- 加载完成-文章详情 -->
      <div v-else-if="article.title" class="article-detail">
        <!-- 文章标题 -->
        <h1 class="article-title">{{ article.title }}</h1>
        <!-- /文章标题 -->

        <!-- 用户信息 -->
        <van-cell class="user-info" center :border="false">
          <van-image
            class="avatar"
            slot="icon"
            round
            fit="cover"
            :src="article.aut_photo"
          />
          <div slot="title" class="user-name">{{ article.aut_name }}</div>
          <div slot="label" class="publish-date">{{ article.pubdate | relativeTime }}</div>
          <!-- 关注组件 -->
          <follow-user class="follow-btn"
          v-model="article.is_followed" :user-id='article.aut_id' />
          </van-cell>
        <!-- /用户信息 -->

        <!-- 文章内容 -->
        <div class="article-content markdown-body" ref="article-content" v-html="article.content"></div>
        <van-divider>正文结束</van-divider>
        <!-- 文章评论列表 -->
        <article-comment :source='article.art_id' @onload-success='totalCommentCount = $event.total_count' :list='commentList' @reply-click='onReplyClick'  />
        <!-- /文章评论列表 -->
        <!-- 底部区域 -->
    <div class="article-bottom">
      <van-button
        class="comment-btn"
        type="default"
        round
        size="small"
        @click="isPostShow = true"
      >写评论</van-button>
      <van-icon
        name="comment-o"
        :info="totalCommentCount"
        color="#777"
       />
      <!-- 收藏组件 -->
      <collect-article class="btn-item" v-model="article.is_collected" :article-id='article.art_id' />
      <!-- 点赞组件 -->
      <LikeArticle class="btn-item" v-model="article.attitude" :article-id='article.art_id' />
      <van-icon name="share" color="#777777"></van-icon>
    </div>
    <!-- /底部区域 -->
    <!-- 发布评论的弹出层 -->
    <van-popup v-model="isPostShow" position="bottom" round>
      <CommentPost :target='article.art_id' @post-success='onPostSuccess'/>
    </van-popup>
      </div>
      <!-- /加载完成-文章详情 -->

      <!-- 加载失败：404 -->
      <div v-else-if="errStatus === 404" class="error-wrap">
        <van-icon name="failure" />
        <p class="text">该资源不存在或已删除！</p>
      </div>
      <!-- /加载失败：404 -->

      <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div v-else class="error-wrap">
        <van-icon name="failure" />
        <p class="text">内容加载失败！</p>
        <van-button class="retry-btn" @click="getArticleById">点击重试</van-button>
      </div>
      <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
    </div>
    <!-- 评论回复弹出层 -->
    <van-popup v-model="isReplyShow" position="bottom" style="height: 95%" round>
     <CommentReply v-if="isReplyShow" :comment='currentComment' @close='isReplyShow = false' />
    </van-popup>
  </div>
</template>

<script>
import { getArticleById } from '@/api/article'
import { ImagePreview } from 'vant'
import FollowUser from '@/components/follow-user'
import CollectArticle from '@/components/collect-article'
import LikeArticle from '@/components/like-article'
import ArticleComment from './components/article-comment'
import CommentPost from './components/comment-post.vue'
import CommentReply from './components/comment-reply.vue'
export default {
  name: 'ArticleIndex',
  components: {
    FollowUser,
    CollectArticle,
    LikeArticle,
    ArticleComment,
    CommentPost,
    CommentReply
  },
  // 给所有的后代组件提供数据
  provide: function () {
    return {
      articleId: this.articleId
    }
  },
  props: {
    articleId: {
      type: [Number, String, Object],
      required: true
    }
  },
  data () {
    return {
      article: {}, // 文章数据
      loading: false,
       errStatus: 0, // 失败状态码
       followLoading: false,
       totalCommentCount: 0,
       isPostShow: false, // 控制评论弹层的显示状态
       commentList: [], // 评论列表
       isReplyShow: false,
       currentComment: {} // 当前点击回复的评论项
    }
  },
  computed: {},
  watch: {},
  created () {
    this.getArticleById()
  },
  mounted () {},
  methods: {
    async getArticleById () {
      this.loading = true
      try {
        const { data } = await getArticleById(this.articleId)
        this.article = data.data
       // 初始化图片点击预览
        setTimeout(() => {
          this.previewImage()
        }, 0)
      } catch (error) {
        if (error.response && error.response.status === 404) {
          this.errStatus = 404
        }
        this.$toast('获取文章详情失败，请稍后再试')
        console.log(error)
      }
      this.loading = false
    },
    previewImage () {
      const articleContent = this.$refs['article-content']
      const imgs = articleContent.querySelectorAll('img')
      const images = []
      imgs.forEach((img, index) => {
        images.push(img.src)
        img.onclick = () => {
          ImagePreview({
            // 预览图片的地址数组
            images,
            // 起始位置，从0开始
            startPosition: index
          })
        }
      })
    },
    onPostSuccess (data) {
      // 关闭弹层
      this.isPostShow = false
      // 将发布内容显示到列表的顶部
      this.commentList.unshift(data.new_obj)
    },
    onReplyClick (comment) {
      this.currentComment = comment
      this.isReplyShow = true
    }
    }
}
</script>

<style scoped lang="less">
@import './github-markdown.css';
.article-container {
  .btn-item {
    border: none;
      padding: 0;
      height: 40px;
      line-height: 40px;
      color: #777777
  }
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
   /deep/ .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>
